validate

To be valid the token must be signed by the passed in certificate and
the certificate must be the one referred to by the SigningCertificate
attribute included in the hashed attributes of the token. The
certificate must also have the ExtendedKeyUsageExtension with only
KeyPurposeId.id_kp_timeStamping and have been valid at the time the
timestamp was created.

A successful call to validate means all the above are true.

Parameters:

sigVerifier - the content verifier create the objects required to verify the CMS object in the timestamp.